Science Quiz

A student wishes to check the upper and the lower fixed points on a Celsius scale thermometer. She has four beakers P, Q, R, and S. Beaker P contains a mixture of ice and salt. Beaker Q contains a mixture of ice and water. Beaker R contains boiling salt solution. Beaker S contains boiling water. Which two beakers should she use to check the fixed points?

• P and R

• P and S

• Q and R

• Q and S

A gas is stored in a sealed container of constant volume. The temperature of the gas increases. This causes the pressure of the gas to increase. What happens to the gas molecules during this pressure increase?

• The average kinetic energy of the molecules increases.

• The average separation of the molecules decreases.

• The average separation of the molecules increases.

• The volume of each molecule increases.

Which statement describes what happens as ice at 0°C starts to melt to become water?

• Energy is absorbed and the temperature remains constant.

• Energy is absorbed and the temperature rises.

• Energy is released and the temperature remains constant.

• Energy is released and the temperature rises.

The melting points of ethanol and mercury are shown. Which substance has a lower melting point?

• Ethanol

• Mercury

Which of these two liquids is/are suitable to use in a liquid-in-glass thermometer to measure temperatures of –50 °C and –120 °C?

• ethanol only

• ethanol and mercury

• mercury only

• neither ethanol nor mercury

An engineer wants to fix a steel washer on to a steel rod. The rod is just too big to fit into the hole of the washer. How can the engineer fit the washer on to the rod?

• Cool the washer and then place it over the rod.

• Cool the washer and rod to the same temperature and then push them together.

• Heat the rod and then place it in the hole in the washer.

• Heat the washer and then place it over the rod.

Where must the bulb be placed so that 0 °C can be marked on the stem?

• in a freezer

• in pure boiling water

• in pure cold water

• in pure melting ice

State what is meant by the specific heat capacity of a substance.

• The amount of heat required to raise the temperature of a unit mass of the substance by one degree Celsius.

• The amount of heat required to change the state of a unit mass of the substance.

• The total heat content of a substance.

• The temperature at which a substance changes from solid to liquid.

State what happens to the molecules of a gas in a sealed container when the temperature of the gas is increased.

• The molecules move faster and collide more frequently.

• The molecules slow down and collide less frequently.

• The molecules stop moving.

• The molecules escape the container.

A quantity of gas is contained in a sealed container of fixed volume. The temperature of the gas is increased. Which of the following are reasons why the pressure of the gas increases?

• The molecules move faster and collide more frequently with the walls of the container.

• The molecules move slower and collide less frequently with the walls of the container.

• The molecules move faster and collide with less force with the walls of the container.

• The molecules move faster and collide with more force with the walls of the container.